1. Field of the Invention
The present invention relates to electrical card connectors for electrically connecting electrical cards with printed circuit boards, and particularly to card connectors having polarization mechanisms to prevent cards from being incorrectly inserted into the card connectors.
2. Related Art
With ongoing developments in electronics and communications, more and more electrical cards are being designed to satisfy all kinds of needs. As a result, different kinds of electrical card connectors are being developed. Most card connectors have a polarization mechanism to ensure that a card is correctly inserted into the card connector. If the card is incorrectly inserted, the polarization mechanism prevents the card from being fully inserted.
Conventionally, a bevel is formed on an electrical card, and a corresponding electrical card connector has a ramp portion matching the bevel. When the card is inserted into the connector, the bevel must mate with the ramp; otherwise, the ramp prevents full insertion of the card. A pertinent card connector is disclosed in Japanese Patent Application No. 11-66247 by Kokai.
The polarization mechanism of the Kokai patent application can prevent a card from being improperly inserted. However, damage to the contacts of the connector may occur, because a front edge of a wrongly inserted card can press against the contacts. Moreover, forcible improper insertion can easily damage the card.
Accordingly, an electrical connector with an improved polarization mechanism which can prevent the front edge of an improperly inserted card from damaging the contacts is desired.
An object of the present invention is to provide an electrical card connector which ensures that an electrical card can be inserted thereinto correctly and safely.
To achieve the above object, an electrical card connector in accordance with a preferred embodiment of the present invention includes a shell, an insulative body, a plurality of contacts mounted in the insulative body, an ejection mechanism and a polarization mechanism. The shell covers the insulative body and the contacts. The ejection mechanism is mounted in the insulative body, and includes a slide block. The polarization mechanism includes a guiding groove defined in the shell and an elastic piece attached to the slide block. The elastic piece has an arcuate engaging portion and a blocking portion. The guiding groove forms a blocking edge to abut against the blocking portion, thereby preventing rearward movement of the slide block when a card is incorrectly inserted. When the mating card with a notch cut in at a side thereof is correctly inserted into the connector, the notch receives the engaging portion therein, allowing the blocking portion to move out of alignment with the blocking edge, so that the card can be fully inserted into the connector successfully. When the card is incorrectly inserted into the connector, the blocking portion is blocked by the blocking edge.
These and additional objects, features and advantages of the present invention will become apparent after reading the following detailed description of a preferred embodiment of the invention taken in conjunction with the appended drawings.